The presence of contaminants in drinking water is increasing at alarming rates. Examples of typical contaminants found in drinking water are fluoride and iron, because we’re unable to see them with our physical eyes however, there’s a tendency to overlook the import of constant ingestion of them on our bodily systems.
In this article, you’d get to know why they are harmful and what you can do to eradicate them from your home’s drinking water system as a whole.
Fluoride in Drinking Water
For most of us, we have little to no control over whether fluoride is added to our drinking water for the city source, and if so, how much is added. Now, that’s scary because of the potential toxicity of fluoride.
Let’s get a wholesome idea of the element fluoride.
What is Fluoride Comprised Of?
When fluoride as an element combines with other minerals in rocks/soils, the result is a mixture of salt compounds that can be deposited in water but also found in toothpaste and food- and is easily retained in our bones and teeth. The danger with fluoride comes at higher concentrations in which it is toxic and can cause poisoning on inhalation, ingestion or contact with skin.
If Fluoride Can be Toxic, Why is it Then Added to Our Water?
Water fluoridation is common in many American cities, and it involves an automatic addition of the element to water supplies. The major aim of fluoride addition is to help reduce tooth decay in the general populace – which is a benefit it offers at low levels in the saliva(another reason for which fluoride is found in toothpaste). However, when you ingest heavily fluoridated water, you stand the risk of harm e.g. vomiting, mottling of dental enamel, bone pain, fractures, organ damage and even death. A Harvard study, adding credence to the suspicions of fluoride’s toxic effects proved that there was a correlation between reduction in IQ and increased fluoride levels in drinking water.
I Want to Remove Fluoride from my Drinking Water! How can I Achieve this?
Thankfully, there are a couple of efficient drinking home water filter systems that help in fluoride removal from your water, of which HomeMaster water filters are a popular choice, too.
Other methods through which fluoride can be removed from water include: distillation (which tends to take a lot of time for water purification) , activated alumina use and bone char usage.
- Reverse Osmosis: Via the use of a semi-permeable membrane, up to 97% of fluoride is filtered out of the drinking water. Can produce large amounts of drinking water for families; HomeMaster water filters are a popular choice, too.
- Distillation: Via this method, a water distiller boils water in one chamber and it captures the purified water vapor in another chamber- thus getting rid of contaminants. Is best used for small families that need small-moderate amounts of fluoride-free water since it is time consuming.
- Bone Char: This carbon type, made from charing cattle bones works like human bones in attracting fluoride and trapping it. Can be used to filter water in the whole house.
- Activated Alumina Oxide: Made from natural corundum minerals, this fluoride removal system is often used for large amounts of water too and it captures fluoride through an adsorption process.
Iron in Drinking Water
Iron, an abundant element which comprises 5% of the earth’s crust is known to contribute red/brown color to different pigments, rocks and soil; as well as the red color to blood cells. The means of entry of iron into water is via its dissolution in rocks/sediments, therefore adding an unpleasant metallic taste as well as an unappealing color to the water.
Major Forms of Iron in Drinking Water
Iron has 2 main forms in water: ferrous and ferric forms.
While ferrous iron doesn’t precipitate as a solid when it dissolves in water (therefore it doesn’t add any unpleasant color to the water), it can give an annoying dark color to food when used in cooking. Ferric iron, the oxidized form of iron precipitates in water and gives it a reddish-brown color.
Thus, when iron-containing minerals come in contact with water in which all of the dissolved oxygen has been used up, ferrous iron enters into the water. For ferric iron however, its entry point is usually as small particles of iron-containing minerals, or when ferrous iron is oxidized.
When there is corrosion of iron/steel pipes, an increase in the iron content of water can also be observed.
How Much of Iron Intake is Safe?
At iron concentrations of about 0.3mg/L, it has been noted that hard-to-remove stains are deposited on sinks, tableware, laundry and even plumbing pipes. Also, certain bacteria types bind to iron and create smelly, yellowish/reddish-brown biofilms, potentially causing clogs in plumbing pipes.
In the human body, large iron doses can be deadly- but in moderate amounts, except for those with health conditions like haemochromatosis (where iron is absorbed in larger than usual amounts by the GIT), iron is rarely harmful at doses below 0.3mg/L. Above this level, there starts to be problems with the color and taste of water, as well as with overall safety of iron intake.
How can Iron be Removed from Drinking Water?
To effectively remove iron from your drinking water, you need to have an idea on what the source of the iron is. Might it be because of corrosion? Then raising the water’s pH might be the simple answer.
For dissolved ferrous iron, aeration/filtration, chemical oxidation, water softening, the use of oxidizing filters and phosphate treatment can work. Solid ferric iron is best treated with oxidizing filters e.g. manganese greensand, or with chemical oxidation e.g. chlorination/filtration.
Iron bacteria on the other hand is eradicated via shock chlorination (adding high chlorine levels) followed by continuous chlorination (adding lower chlorine levels). Finally, for organic iron, the best water treatment is achieved with the use of activated carbon filters after which you use oxidizing filters.
In summary, iron removal from water can be conducted via:
- Aeration/ Filtration: Using oxygen to oxidize ferrous iron, following which a precipitate is formed in the filter, and discarded.
- Water softening: removes the ferrous iron ions and replaces them with sodium.
- Chemical oxidation: using chemicals like potassium, chlorine, hydrogen peroxide to oxidize ferrous iron.
- Oxidizing/catalyzing filters: made of zeolite (coated with manganese oxide) or manganese greensand. Filter absorbs iron and manganese from the water by converting to oxidized form and subsequently leading to production of precipitate in the filter.
- Phosphate treatment: when ferrous iron reacts with phosphate, it stops the iron from precipitating as solids.